It's interesting to note the process of building the language within my mind, with native speaker materials. A native speaker knows best the most natural way to say something, knows best the grooves of the language, and the more time i sepnd reading and listening to native language, the more these SAME grooves become engrained. Input builds structure, and if i want my structure to be as near native as possible, the input needs to be native. And i agree with Khatz, it's not rrally a creative process, not until youre already at native level. In this sense it is a lot different from artistic creation.